Follow the topics within this article

If there's a crucial lesson that Justin Crump carried over into business from his time with the armed forces, it's "serve to lead" – the brain-teasing motto of the officer training academy at Sandhurst.

"In other words, don't ask people to do what you're not prepared to do yourself," says the business owner, who launched his threat and risk advisory firm, Sibylline, eight years ago. "Entrepreneurs have to be prepared to put in the hard hours. I hate to see founders pay themselves £120,000 a year while their company has no turnover."

Crump did no such thing when starting out, paying himself nothing and grafting 20 hours a day to win enough new business to fund his operation for another few months.

"I was running a company with my hair on fire," remembers the founder, who's the third to be profiled by The Daily Telegraph as part of a series in partnership with Heropreneurs that celebrates the achievements of some of the charity's military members who have started their own companies.

Sibylline offers a wide range of security services, from analytical reports about risky overseas travel to live social media monitoring. Its core offering is its World Risk Register, a data-driven subscription service that provides clients with regular written briefs, trend podcasts, training webinars and global alert forecasts.

"It's about delivering timely, accurate and actionable information," says the entrepreneur, whose 100 core customers are mostly Fortune 500 businesses, but also include sporting events, universities and aid organisations. Tailored to each client, analysis could be country specific (for a company that's entering the Colombian market, for example) or more niche, such as when a firm wants to ensure that its partners are not violating sanctions. "It's all about making them safe and secure, and managing their risks."

With nothing on the shelves, people didn't understand what I was sellingJustin Crump, Sibylline

Crump's military career began when he joined the Royal Armoured Corps reserves aged 17. He describes it as fun, intelligence-led work that taught him a lot about making decisions on the fly and managing small teams.

After graduating, he took a corporate finance job at JP Morgan before being called up by the Queen's Royal Hussars following the 9/11 attacks. He served in Iraq, learning Arabic and running local police forces north of Basra.

Returning home in 2004, he worked first as the Duke of Westminster's personal staff officer, then as an embedded analyst at UniCredit, and finally in threat intelligence.

A desire to strike out and become a leader himself led Crump to form Sibylline in 2010. "You either have job security but deal with the frustrations of working for someone else, or you deal with the anxiety of going it alone," he explains. "Successful entrepreneurs are those who can handle the latter."

But with no money, clients or contacts, it was a tough start. Crump's strategy was to take on very small (mostly freelance) projects, patiently delivering those, and reinvesting the money back into the company. As his bootstrapped business slowly and steadily grew, he would take on larger briefs.

A reputation for being an interesting character helped the founder to secure work. "I could speak and present well; my talent was taking complex things and making them straightforward and entertaining," he says. "I could, for example, spell out what a business needed to know about al-Qaeda and how it affected them in particular."

But it was never a sure thing – especially at first, when Crump's cash-poor company had no tangible products to show off to interested parties. "It was like running an empty shop; people would come in and we would have a great conversation, but with nothing on the shelves, they didn't understand what I was selling."

As a business, it's always better to screw up in practiceJustin Crump, Sibylline

To combat the complex and intangible nature of Sibylline's work, Crump created a series of general, showroom-type tools to show off and tailor later. "People found it much easier to grasp products over concepts," he says, adding that even with something to demonstrate, a sale is far from easy. "It's like insurance, because you're trying to convince people to spend extra money to save money that they don't even know they might lose."

Then there's the rise of the cybersecurity threat in recent years, which makes clients less sure of what they need. "Two years ago, if I said that I worked in security, you would think guards, gates and guns, but now, people think of cyber," he says. "We're well positioned there, but it's a challenge for clients, because they're having a fight internally over who runs that side of things – is it the ex-FBI guy or the chief information security officer?"

A strong team, hired based on cultural fit, has helped Sibylline to overcome these hurdles and build up a solid base of clients. "We look for motivated people who believe in what we do," says Crump, whose company registered turnover of £1.6m last year, and is on course to post sales of £3.2m this year. It acquired the assets of corporate security firm, Aegis Advisory, in 2016 and bought West Sands Advisory in August.

Unlike the other veteran entrepreneurs profiled in this series, Crump is still serving, commanding the Royal Gloucestershire Hussars, a 200-year-old reserve cavalry unit that now forms part of the Army's main battle tank capability.

He still gains valuable business lessons from it. "In the Army, you're taught how to plan, but also how to take advantage on a fluid battlefield, so if you see an opportunity, you strike," he explains. "That agility and manoeuvrability really helped me early on, when we were doing a lot of testing, learning and iterating."

Also of benefit are the war games that, importantly, simulate failure (or in real terms, death). "On exercises, you can lose and get killed – and you have to do it all again," he says, adding that businesses should never fear testing failure. "Some will never do it, because it might demoralise staff or make the leader look bad, but it's always better to screw it up in practice."

He neatly sums it up through another military mantra: "Sweat in training saves blood in wartime."

The Telegraph is an official media partner of Heropreneurs, a charity that specialises in helping people from the armed forces to grow their own businesses